Co-modulating CO Adsorption and Interfacial Water Dissociation through a Lewis Acid Site Boosts Industrial CO ₂ -to-Ethylene Conversion

Copper-based electrocatalysts have shown great potential for electrolytic CO₂ reduction (CO₂RR) to value-added multi-carbon products but suffer from poor selectivity and activity due to the uncontrollable CO adsorption and sluggish C-C coupling kinetics. Herein, we develop a dopant-driven interfacial engineering strategy by incorporating chromium (Cr) into copper oxide, which <i>in situ</i> reconstructs to Cu-CrO_<i>x</i> heterointerfaces under CO₂RR conditions. Combined experimental and theoretical analyses reveal that Lewis acidic CrO<i>_x</i> clusters tailor the electronic structure of Cu sites, thereby strengthening the CO adsorption and accelerating C-C coupling. The Cu-CrO<i>_x</i> interface also promotes water dissociation to supply active hydrogen species for multiple hydrogenation steps. The optimized catalyst achieves a 59.2% faradaic efficiency for ethylene and maintains stable operation for over 110 h at 2.45 V in a membrane electrode assembly electrolyzer. This work highlights dopant-enabled interfacial engineering as a versatile strategy for steering CO₂RR activity and selectivity toward multi-carbon products, offering mechanistic insights that advance the field.